Shared-media communication networks, such as wireless networks or power-line communication (PLC) networks (a type of communication over power-lines), provide an enabling technology for networking communication. Shared-media, however, is generally a physical medium that is strongly affected by environmental conditions that change over time. Some examples include temporal changes in interference (e.g., other wireless networks or electric appliances), physical obstruction (e.g., doors opening and/or closing or seasonal changes in foliage density of trees), and propagation characteristics of the physical media (e.g., temperature or humidity changes). The time scales of such temporal changes can range between milliseconds (e.g., transmissions from other wireless networks) to months (e.g., seasonal changes of outdoor environment).
It is not rare in many types of networks for each node to have a very large number of neighbors that are potential next-hops in a routing topology. As defined generally by routing protocols for these types of networks, links are considered independently of each other. Consider a set of neighbors in a wireless environment: if a node N has the choice between K neighbors, it will select one or more next-hop routes based on the advertised cost, the Objective Function, and possibly constraints.
That said, the shared physical medium naturally leads to “fate-sharing” between different links. It is common to have groups of links that are affected by the same source of perturbation. Neglecting the notion of fate-sharing in the route selection process results in potentially selecting a set of next-hop routes that are affected by the same source of perturbation. As a result, when link connectivity fails for one next-hop route, the same could be true for all other next-hop routes that serve as a backup. This may also be an issue when using “1+1” protection where traffic is duplicated over diverse paths. Searching for new next-hop routes is a time consuming process and is undesirable.